Say there are two objects, A and B. A is moving with X velocity and B is at rest. Upon collision, what factor determines whether A will rebound off of B and B will stay at rest. Also, what determines if the two objects will "stick" together or move in the same direction as A? I believe it has mostly to do with B's mass, but I've tried using the law of momentum conservation and that didn't work out too well (but I might've been doing it wrong).